[Subclavian Artery Hemorrhage Related to Everolimus in a Patient with Recurrent Breast Cancer--A Case Report].

A 53-year-old woman underwent breast-conserving surgery for right breast cancer (invasive ductal carcinoma, T1cN0M0, ly+, stage ⅠA, ER+, PR+, HER2-) 5 years previously. During treatment with tamoxifen, massive recurrence in the axillary lymph nodes was found. First- through fourth-line chemotherapy were tried, but they all failed. Everolimus and exemestane were administered, resulting in rapid shrinking of the tumor, but the patient developed sudden severe bleeding from the subclavian artery. Hemostasis was achieved with artery stenting. The patient also developed a thoracic duct-cutaneous fistula. The patient died from tumor regrowth 6.5 months after her first everolimus treatment. Treating tumors involving major vessels with everolimus can cause severe bleeding after rapid shrinking of the tumor.